Lubricant containing bis (trichloromethyl) benzene



United States Patent 3,179,592 LUBRICANT CONTAINING BIStTRI- CHLOROME'I'HYDBENZENE Robert K. Smith and Paul J. Welsh, Springfield Township, Pa., assignors to Diamond Alkali Company, Cleveland, Ohio, a corporation of Delaware No Drawing. Filed Mar. 20, 1963, Ser. No. 266,522

11 Claims. (Cl. 252-58) This invention relates to an improved extreme pressure agent and to a lubricant containing it. More particularly, this invention concerns an oil-soluble additive material capable of imparting extreme pressure, increased load carrying capacity and anti-wear properties to lubricating oils without upsetting other desired characteristics of the lubricant. i

It is well known that the high pressure occurring in certain types of gears and bearings may cause a film of lubricant to rupture with consequent damage to the machinery. It has been shown that base lubricants such as mineral oil and/or synthetic oil can be improved with regard to their protective effect, particularly on rubbing surfaces by the addition of certain substances, so that excessive wear, scufiing and seizure, which normally folloW a break in the film of the lubricant, can be prevented even under very unfavorable pressure and speed conditions. Lubricants possessing the highly desirable prop erty are called extreme pressure lubricants.

Extreme pressure lubricants have found extensive use as gear lubricating fluids, such as in the lubrication of gear differentials of trucks and other vehicles. The lubrication of gears demands lubricants of special qualities particularly high lubricity and high film strength. When a lubricant is compressed between two moving metallic surfaces, high film strength is necessary to prevent direct metal-to-metal contact of said surfaces, with consequent welding. The extreme pressures to which lubricants are subjected when compressed between hypoid gear surfaces cause a rise in internal heat which is augmented by any heat from friction generated by lack of point-lubricity. It has been found that oleaginous liquid lubricant bases such as mineral lubricating oils, esters, whether natural esters, for example, castor oil or sperm oil or synthetic ester lubricants and other synthetic lubricants alone are unsatisfactory in that they do not have the required high lubricity and high film strength and consequently allow scoring and welding of gears on continued use.

Many types of additives have been prepared and added to extreme pressure lubricant formulations for the purpose of augmenting film strength, lubricity and other desired characteristics. Fatty oils and fatty acid esters, for

example, have been added in various amounts and combinations to hydrocarbon oil fractions, particularly for the purpose of furnishing oiliness, that is to say, high lubricity. It has also been found that when sulfurcontaining compounds are added to extreme pressure lubricants, film strength is somewhat increased, and recent formulations have combined ester additives with sulfur by sulfurizing said esters to provide both lubricity and film strength of high degree. Still more recently, it has been discovered that the use of phosphorus in combination with the sulfur-containing ester additives has further augmented desired fihn strength to a level of highly satisfactory performance. Thus, oils and fatty esters may have incorporated therein phosphorus and sulfur by reaction with any one of a number of phosphorus sulfide compounds, such as phosphorus sesquisulfide. The increased performance of phosphorus and sulfur-containing esters as additives for extreme pressure lubricants, when compared with sulfur-containing esters as additives for extreme pressure lubricant-s, may be seen in that the former are effective for transmissions operating at both low speed and high torque, and at high speed and low torque, whereas esters which have only been sulfurized and which are considered suitable extreme pressure additives exhibit in the extreme pressure lubricants satisfactory performance only under conditions of low speed and high torque.

It has now been discovered that satisfactory extreme pressure and anti-Wear lubricants can be obtained by incorporating into a base lubricant aromatic compound possessing the trichloromethyl grouping, i.e., -CCI More particularly, the present invention resides in an extreme pressure lubricating composition comprising a major amount of base lubricating oil and a minor amount sufficient to impart extreme pressure characteristics to the base oil of an additive having the following structural formula:

[( 2) aly wherein R is an aromatic hydrocarbon ring, preferably C H f-- indicates a fused ring relationship (two carbon atoms common to two aromatic nuclei, e.g., as in naphthalene); m is generally 0 to 1 or more; x is an integer of from about 0 to 4 or more, preferably from 0 to 2 and y is an integer of from about 2 to 6, preferably from 2 to 3. The preferred aromatics, however, include trichloromethylated benzenes corresponding to the above formula when m is 0; x is 0 and y is 2. Such preferred aromatics include, for instance, a,a-hexachloro-p-xylene; a,a hexachloro-m-xylene; a,a'-hexachloro-o-xylene and mixtures of such isomers.

The additive is prepared by the photochemical chlorination of the appropriate xylene isomer or mixtures of the same giving the corresponding polychloro derivatives by the replacement by chlorine of the side-chain hydrogen. Such methods are described in French Patent 798,727 and Chemical Abstracts, 49, 14670 f. The preparations of the additive are subject to variation as to the relative amounts of the respective reactants employed. Generally, the chlorine will be employed in a molar excess relative to the xylene, usually in amounts of up to about 8 moles of chlorine per mole of xylene. The reaction is conducted in the presence of any suitable ultra violet light as a source of photoactivation such as a mercury vapor lamp, for example, a 360-watt GE. Uviarc mercury vapor lamp in a single-wall Pyrex well or a 450-watt Hanovia mercury vapor lamp in a double well, with the lower half of each well made of Corex type D glass to transmit ultraviolet wave lengths.

The reaction may be accelerated and/or its course controlled by the application of heat to the reaction mixture. The reaction temperature may vary from about 70 C. to about 150 C. Excessively high temperatures may cause some decomposition and are thereby undesirable. The use of lower temperatures merely reduces the rate of reaction. Temperatures between about C. and about C. are preferred. Usually the reaction temperature The time of reaction may vary from about 6 to about 35 or more hours, depending on the temperature employed, with a preferred maximum time of about 30 hours.

EXAMPLE 1 To a parafiinic base mineral oil having the following characteristics:

. Gravity 26-2-8 Pressure techniques may also be utrhze to pr p the v18 p 100410 extreme pressure addit ve of the present lu n r pl h i p 3 0 sures are generally maintained in the l actlon V ss Wlth- Firepoint O F. 410 in the range of about to a t 0 9 pfeffiffrlbly p point, e F a 9 to 3 reactants may be i is added the extreme pressure additive of the present innltered n order to remove iron from the raw materia s 10 vention in amounts of 1% and 2% by welght reSPec. Whlch if present durmg e dlscolola' tively. The various formulations containing the additive tion of the batch, promotes ring chlorination and decomare as follows: position and reduces light transmission. Also a sequespercent 1 Composition A: tenng agen may be s to sequester traces of Iron W119}! Pmm base mineral oil, 100 SUB F 100 remains in the reactor charge. A suitable sequestering 5 Z agant includes triphenyl Phosphate r l ti riii b se mineral o l 100 SUS 100 F or;

After the reaction is completed, the react on vessel 18 a al-Hexaohloro-p-xylone (M.P.107-110 C.) 1 swept with an inert gas such as air or nitrogen to render To?) the system substantially free of HCl gas. The product 2 i Composition 0: 1s then dissolved in a solvent such as acetic a l m th nol, 20 Paramn base mineral on, 100 SUS F 99 ethanol, isopropanol, etc. and cooled to about 20 C. and a aLHxachlor-o-p-xylene (crude, lvLP. 102-105 o.) 1 filtered resulting in a recovery of a substantially pure hexachloroxylene product. The reaction between the chlorine and xylene may be effected in either a batchwlse, i F 2 mineral on 100 SUS F" 99 an intermittent or a continuous manner. 25 g y ir n The case oil in our improved extreme pressur lubricant Phenyl pentacmomethanm 6 may comprise any petroleum or mineral lubricating oil n gna aj,a.Pentach1 m.0-xylen 5 fraction, for instance, a solvent extracted or solvent re- 3% fined oil obtained in accordance with conventional meth- E a Composition ods of solven refin ng lu n mg 0 1 f n, l rw 3o 1.3mm base mineral oil, 100 SUS @NOOF Q9 mg oils have viscositics from about to 1000 or more a nexaeh om-ms ene s2 0 a a,a -Hexach oro-p-xy anon.

o.U.S. at 100 F. The base oil may be derived from Phenylpenmchlomethane 3 1 parafliiuc, naphthenic, asphaltic or mixed base crudes, a,a,a,a,a-Pontachloro-o-xylene 3 and if desired, a blend of solvent-treated Mid-Continent neutrals and Mid-Continent bright stock may be em- 35 r Y a t Composiiou ployed. Also contemplated are ester base lubricants such Paramn base mineral on, 100 SUS F 99 as the synthetic esters, for example, diesters or complex a,ai-Hexaohloro-p-xyleno s4} 1 esters, such as di-Z-ethylhexyl sebacate. Aside from the fiexachlom'm'xylone 15 hexachloroxylene additive the base oil is usually the essen- 100 tial balance of the composition. However, the cornposi- 4O composition G: a tion may also contain minor amounts of other additive Para bnsemmcralol ,100 SUS @100 F- 9s a,a-Hexaehloro-p-xylene(107-110 C.) 2 agents such as pour depressor s, viscosity index rmprovers, anti-oxidants, foam inhibitors, etc. 7 100 The additives of the present invention have been found The results from the extreme pressure tests are given in effective in the base lubricants in amounts ranging between 45 Table I.

Table I Composition A B C D E F G Extreme pressure test:

4-13 all (weld point, kg.) 90 224 224 224 224 224 Falox (failed at load, lbs.) 500 000 000 250 250 500 Jaw Jaw Jaw load load (lbs) v. Torque load (lbs) v. Torque (lbs) v. Torque Almen 22 Failed 1 30 26 1 30 21- Cornoll 4, 500 45 1 Full load.

about 0.1 to about 10, preferably between about 0.5 to 5, weight percent.

In order that those skilled in the art may more completely understand the present invention and the preterred methods by which the same may be carried into Using the additive of the present invention in a base mineral oil, the weld point using the Shell 4-ba1l EP. test is increased by about Also, the base oil fails at a load of less than about 500 pounds using the Falex E.P. test, whereas when 1% of the additive is present the composition fails at loads of from about 3000 to about 3500 pounds. Further, using the Almen El. test on the base oil containing 1% of the additive a torque reading of 26 at a full load of 30 pounds is obtained and when 2% of the extreme pressure additive is added to the base oil a torque reading of 21 at a full load of 30 pounds is obtained, whereas the base oil without the additive when tested on the Almen E.P. tester gives a torquereading of 30 at a load of 20 pounds and fails at 22 pounds. When 1% of the extreme pressure additive is added to the paraflinic base oil and tested on the ER Cornell tester a low torque of 45 at 4500 pounds jaw load is obtained.

EXAMPLE 2 To a 3% emulsion containing:

1 Percent 2-methyl 2,4-pentanedio1 9.6 Straight chain fatty acid (a tall oil fatty acid-aver. carbon chain length alkyl carboxylic acid containing unsaturated componcnts):

Visc. 100 F., SUS 93 Specific gravity 25/25 0.0005 Iodine Value 130-140 Saponification No 190-195 Flash point, F- 38 Fire point, F Pour point, F +37 Paraflim'c base oil: Visc. 100 F Flash point, Fire point, F Pour point, F.. Sulfur content Alex 1516 (amine derivative of an oxidized parafiln wax):

Visc. 100 F., SUS- Specific gravity 127 Pour point, F.. Flash point, F Sterox AS-l (adduct of nony ph Water Condensate:

Diethanolnmine .parts Straight chain naphthenic based fatty acid (Aver. Cm carbon chain length alkyl carboxylic acid containing unsaturated components): Acid N 0. 160-180. ,parts i is added 2% by weight of a,a-hexachloro-p-Xylene (MP.

107-110 C.) and the final mixture tested on the Almen tester.

Table II ALMEN E.P. TEST The data in Table 11 show that the additive of the present invention gives a torque reading of 17 at a load of 30 pounds (full load), indicating the composition possesses excellent extreme pressure characteristics for a cutting oil.

EXAMPLE 3 To the following composition:

Percent Suliurized fatty esters of lard oil (IO-11% sulfur):

Vise. 100 F., SUS 800-900 35 Cgnoritnated paraffin Wax (aver. Can-3o carbon chain eng Gravity 60 F- 23-25 Visc.-@ 100 F., SUS 4, 000 210 F., 8118.... 100-180 Percent chlorine"--- 41-43 Saponifieation No 172 Sulfur, Wt. percent 0. 042 20 Naphthenic base mineral Visc. 100 F., SUS 100-110 Gravity. 21-25. Flash point, F min- 330 Pour point, F... "max" 0 21 Pine oil:

Gravity 68 F. 20. 5'21. 5 Flash point, F 172 3 N aphthenic base mineral 0 Vis.@ 100 F., 2, 150-2, 200 210 F., SUS 80-90 Gravity 18.0 Flash point, F 450 Fire point, F 500 Pour point, F +15 Sulfur, wt. percent 0.28 21 Composition (without additive) 6 is added 3% by weight of a,a'-heXachloro-p-xylene (MP. 107 -110" C.) and the final mixture tested on the Almen tester for E.P. characteristic. Also, the above composition is tested for its properties as a cutting coolant by Socony Mobils tapping test method as described in United States Steel Corporation, National Tube Divisions bulletin, copyright 1956 on page DM-61. This test consists essentially in placing a test bar in a. vise on a turntable of a drill press and tapping a hole in the test bar with the drill lubricated with the test coolant. A torque arm attached to the turntable actuates a spring scale and reports the torque for each tap. The average torque of 30 runs made with five diiferent taps is recorded and compared with the average torque of a known reference oil. The percent efficiency of the coolant to be tested is the net result. Table III presents comparative data showing the improvements which are obtained with the above-described composition with and without the additive of the present invention.

Table III pp efIiciency, percent Almen test Failed at 28 pounds. 83 Oomposition+3% a,a-hexa- Full load 102 ehloro-p-xylene.

The above formulation without the additive of the present invention gives a tapping efficiency of 83% and fails at 28 pounds on the Almen tester, whereas the formulation with 3% a,a-heXachloro-p-xylene (M.P. 107- 110 C.) gives a tapping etficiency of 102% and withstands a full load on the Almen E.P. tester.

EXAMPLE 4 To the following composition:

Percent Naphthenic base mineral oil:

Visc. 100 F., SUS--- 200211 Gravity 1921 Flash point F 365 Pour point, F max.. 0 Sulfur, wt. percent. 0. 4 Di-tertiary nonyl polysulfidc:

Vise.-

0---..- 5. 9 Specific gravity Total sulfur, wt. percent. 36. 5 Active sulfur, wt percent. Calc. mol. wt 414. 8 6 Straight chain fatty acid (a tall oil fatty acid-aver.

Om carbon chain length alkyl carboxylic acid containing unsaturated components):

Visc. 100 F., SUS

Four percent by weight of a,a-heXachloro-p-Xylene (MP. 107 -110 C.) is added and the formulation is characterized by the following properties:

The Almen and Cornell extreme pressure tests are made on the above formulation containing 4% of the extreme 2 pressure additive of the present invention and the results are presented in Table IV.

Table IV Loads (lbs) Torque Cornell Almen Cornell Almen 750 6 12 17 1, 000 8 16 1, 250 10 20 23 1, 500 12 2O 24 1, 750 14 21 2, 000 16 23 25 2, 250 18 24 25 2, 500 20 26 25 2, 750 22 31 26 3, 000 24 32 26 3, 250 20 26 3, 500 28 53 26 3, 750 30 55 26 4, 000 Fail 4, 250 4, 500

Four percent by weight of a,a'-hexachloro-p-xylene in the above formulation gives a torque of 55 at 3750 pounds jaw load on the. Cornell tester and a torque of 26 at a load of 30 pounds on the Almen tester.

EXAMPLE 5 A further example of the effectiveness of the present additive as an extreme pressure agent can readily be seen by the addition of 1% by weight of a,a'-hexachloro-pxylene (MP. 107 -110 C.) to the following gear lubricant.

Naphthenic base mineral oil:

Initial boiling point, F Specific gravity Percent Aniline point"; min. 185 Kinematic viscosity- 32 F 10. 5G a F 3. 82 Flash point, F 210 15 Emolein 2957 (didsooctylazelate):

Kinematic vise. 0 F 12 7 Specific gravity 25 0.....

Pour point, F 41 Emolein 2910 (2-ethyihexylpelargonatc) 41 Acryloid HF 866 1 7 Pentachlorophenyl mercapto acetic acid 1 Viscosity index improver comprising an acrylatc polymer produced by Rohm dz Haas. The results from Tirnken & Cornell extreme pressure tests are given in Table V.

Table V It is to be understood that although the invention has been described with specific reference to particular embodiments thereof, it .is not to be so limited since changes and alterations therein may be made which are in the full intended scope of this invention as defined by the appended claims.

it is claimed:

1. A lubricating composition consisting essentially of a major amount of oil of lubricating viscosity and a minor amount sufiicient to improve extreme pressure characteristics of a compound having the following structural formula:

2. The composition of claim 1 wherein the oil of lubricating viscosity is a mineral lubricating oil.

3. The composition of claim 1 wherein the extreme pressure compound is present in amounts between about 0.1 to 10 Weight percent.

4-. A lubricating oil composition consisting essentially of a major amount of oil of lubricating viscosity and a minor amount sufiicient to improve extreme pressure characteristics of bis(trichloromethyl)-p-benzene.

5. The composition of claim 4 wherein the oil of lubricating viscosity is a mineral lubricating oil.

6. The composition of claim 4 wherein the extreme pressure compound is present in an amount between 0.1 to 10% by weight.

7. The composition of claim 4 wherein the extreme pressure compound is present in amounts between about 0.5 to 5 weight percent.

8. A lubricating oil composition consisting essentially of a major amount of oil of lubricating viscosity and a minor amount sufiicient to improve extreme pressure characteristics of a mixture of bis(trichloromethyl)-pbenzene and his (trichloromethyl)-m-benzene.

9. The composition of claim 8 wherein the oil of lubricating viscosity is a mineral lubricating oil.

10. The composition of claim 8 wherein the extreme pressure compound is in an amount between 0.1 to 10% by weight.

11. The composition of claim 8 wherein the extreme pressure compound is present in amounts between about 0.5 to 5 weight percent.

References Cited by the Examiner UNITED STATES PATENTS 2,261,863 11/41 Whittier 252-58 2,542,286 2/51 Morris et al. 252-58 2,558,079 6/51 Gallsworthy 252-58 2,971,913 2/61 David et al 252-58 3,076,039 1/63 Ayers et a1. 252-58 DANIEL E. WYMAN, Primary Examiner. 

1. A LUBRICATING COMPOSITION CONSISTING ESSENTIALLY OF A MAJOR AMOUNT OF OIL OF LUBRICATING VISCOSITY AND A MINOR AMOUNT SUFFICIENT TO IMPROVE EXTREME PRESSURE CHARACTERISTICS OF A COMPOUND HAVING THE FOLLOWING STRUCTURAL FORMULA: 